I've been using Chrome in iOS since it went on the App Store yesterday, and so far not being able to set it as my default browser doesn't seem to be holding me back too much. It replaced Safari on my dock, and my browser is usually within a single swipe on the multitasking tray at the most. Sure, you'll be thrown into Safari here and there, but that's the case for Mail as well, and I can still enjoy Sparrow.